<html>
<body>
<style>
    table th, table td {
        border: 1px solid #333;
    }
</style>
<table>
    <tr>
        <th colspan="2">T</th>
    </tr>
    <tr>
        <td>11</td>
        <td>12</td>
    </tr>
</table>

<br/>

<table>
    <tr>
        <td rowspan="2">11</td>
        <td>12</td>
        <td rowspan="2" colspan="2">13</td>
    </tr>
    <tr>
        <td>22</td>
    </tr>
    <tr>
        <td colspan="2">31</td>
        <td>33</td>
        <td>34</td>
    </tr>
</table>
</body>
</html>